Absorbent deodorizing, hygienic animal bedding composition and method of manufacture

ABSTRACT

An animal bedding composition and method of manufacture includes cut or shredded pieces of multiple panel corrugated cardboard kraft paper structures having an internal corrugated panel sandwiched between outer panels, and an adsorptive deodorizing ion exchange agent such as a zeolite dispersed throughout the cardboard pieces and carried on outer and inner surfaces of the pieces of cardboard and on outer and inner surfaces of the corrugations to provide a comfortable, hygienic and deodorized floor covering for animal stalls. An automated method of manufacturing the animal bedding composition is also described. The ion exchange agent attaches to surfaces of the corrugated cardboard which serves as a carrier to sanitize and deodorize a stall. The open structure of the cut corrugations provides mechanical load absorption, and a wicking action to aerate moisture from a stall. The ion exchange agent carried by the corrugated pieces removes ammonia odor from urine and provides slow release potassium and, when loaded with ammonium, slow release of nitrogen for agricultural fertilization. Carbon in the kraft paper from which the corrugated cardboard is constructed attracts nitrogen from urine, yielding excellent fertilizing material with rapid biodegradation.

FIELD OF THE INVENTION

[0001] The present invention relates generally to animal beddingmaterials and more specifically to synthetic or preprocessed materialswhich provide a comfortable stall floor covering, and controls moisture,dust and odor in animal housing environments. The invention also relatesto methods of making and packaging animal bedding materials andcompositions.

BACKGROUND OF THE INVENTION

[0002] In a typical managed care facility for large animals such ashorses, cows, etc., stalls are provided for occupancy by one or moreanimals at a time. A critical element of the stall is the flooring orbedding material, as animals spend many hours in a stall as a place forfeeding and resting. Stall floors are typically dirt or concrete or,more recently, rubberized mats. Traditionally, straw or hay isdistributed over the flooring to provide a softer surface and some verylimited absorption of animal waste. In fact, straw and hay are not veryabsorbent, do not have adequate cushioning, and after mixing with animalwaste become very slippery. Stall floors lined with organic materialssuch as straw or hay provide a breeding ground for various fungi whichcan cause respiratory and hoof infections, and induce allergic reactionsin animals and humans. Furthermore, straw and hay do not perform anydeodorizing or odor reducing function. Additives such as hydrated limehave been used with straw and hay as an ammonia/odor control agent. Limehas the disadvantages of high toxicity and is therefore relativelyhazardous, low relative ammonia removal and high relative pH/highalkalinity, rendering the discarded stall material unsuitable for use asa fertilizer. Another disadvantage of straw and hay is the large amountof dust produced when these materials are applied to stall floors. Thisdust is inhaled by the animals causing irritation to the respiratorytract, making them more susceptible to the harmful effects of ammoniainhalation. This is particularly harmful to young animals that spendmuch of their time laying on stall floors where the dust accumulates.Dust is also unsanitary and hazardous and to the breeding and birthingprocesses.

[0003] Alternatively, a number of different materials, organic andinorganic, have been proposed for use as animal bedding material. Amongthese materials are cardboard, shredded paper such as recyclednewsprint, wood shavings and mixtures of these materials. However, anumber of disadvantages arise from use of these alternative materials.For instance, shredded paper is quickly saturated with animal urine andsolid waste. It becomes matted and heavy and thus difficult to removefrom the stall. Bedding material made from wood shavings, on the otherhand, provides support and comfort, but has limited absorptioncharacteristics and can contribute to fungal growth. Wood shavings arealso slow to biodegrade and thus are unsuitable for use as fertilizer.An additional disadvantage of wood shavings is that the individualpieces get tangled in the hair, mane and tail of horses and otheranimals, making cleaning and grooming arduous.

[0004] An additional shortcoming of these prior art animal beddingmaterials is that they do not impede ammonia production in stalls whereanimals are housed. Even in small concentrations, ammonia can pose ahealth problem to animals. It has been shown that atmospheric ammonia isdamaging to the respiratory tract. Even relatively low concentrations ofammonia can diminish airway defense mechanisms, making animals morevulnerable to pneumonia and asthma-like symptoms, leading to a higherincidence and increased severity of pneumonia, particularly in younganimals. Lower weight gains have been observed in animals kept in stallswith ammonia concentrations as low as 25 ppm. Moreover, these materialsoffer no odor masking or odor reduction properties. The odors alsoattract flies and other insects which can carry disease and furtherstress the animals.

[0005] U.S. Pat. No. 5,209,186 describes an absorbent animal beddingmaterial of nodules of cellulose material made from paper pulp producedfrom waste paper. These nodules have a smooth, hard, porous surface andresist breakage during use and handling. However, this material does notsupport the weight of large animals like horses and cows and createsdust when crushed. The nodules are crushed by the weight of these largeanimals, substantially reducing the amount of support and cushionprovided by the bedding material. Also, this material is not easily oreconomically produced and requires numerous manufacturing steps andexpensive mixing and heating equipment. Like the materials describedabove, this animal bedding material does not reduce ammonia productionor odor.

[0006] U.S. Pat. No. 5,372,314 discloses an animal bedding materialproduced by mixing finely shredded cellulose material with calcium oxideand water to form a slurry. The slurry is then neutralized by mixing itwith diatomaceous earth or a non-swelling clay and dried to form theanimal bedding material. This animal bedding material is absorbent, butdoes not inhibit ammonia production and provides no relief from theunpleasant odor produced from animal waste.

[0007] U.S. Pat. Nos. 5,195,465 and 5,352,780 each describe a littermaterial made from compacted cellulose which has been formed intopellets and flaked. Both of these patents suggest adding fungicides,coloring agents, insecticides and herbicides to the flaked material toextend the life of the litter and reduce bacterial and fungal growth.However, neither patent offers a solution to the odor and ammoniaproduction problems associated with other prior art animal beddingmaterials.

[0008] It has also been suggested in U.S. Pat. Nos. 5,133,296 and5,265,561 to combine waste cardboard and wood pallets to make animalbedding material. However, the addition of the wood to the cardboardsubstantially decreases the biodegradability of this material making thebedding material essentially useless as fertilizer after it has becomesaturated with animal waste. Although wood chips are still used on stallfloors, they must be kept separate from straw or hay for disposal asrecycling fertilizer. Compost haulers will not accept stall waste whichincludes wood chips. Stall waste disposal is a critical issue,particularly with large animal care facilities such as zoos, racetracks,and horse farms. A stall material which cannot be economically disposedof cannot be used. This fact eliminates any material which contains woodor any other slow degrading material. Thus, a stall material is neededthat performs hygienic and ergonomic functions in the stall, and abiodegradable fertilizing function in waste form has not been provided.Like the previously described prior art animal bedding materials, thisapproach offers no solution to the odor and ammonia production problemassociated with conventional animal bedding materials.

SUMMARY OF THE PRESENT INVENTION

[0009] To overcome these and other disadvantages of the prior art, it isan object of the present invention to provide an inexpensive andeffective comfortable, absorbent and deodorizing material that is usefulas an animal bedding or stall floor lining material. It is a furtherobject of the invention to provide such a material that is essentiallydust free and inhibits the production of ammonia and reduces theunpleasant odor in areas where animals are housed. It is still a furtherobject of the present invention to provide an efficient method of massproducing an animal bedding material composition having superior ammoniaand odor reduction properties. It is still a further object of theinvention to provide a stall floor covering composition which whensoiled with animal waste provides a rapidly biodegradable fertilizerwith high nitrogen content ready for immediate application byagricultural growers.

[0010] The present invention is directed to an improved animal beddingmaterial having superior cushioning properties and ammonia and odorreduction function. In the preferred embodiment of the invention, theanimal bedding material is comprised of strips or pieces of shreddedcorrugated cardboard combined with an ion exchange agent. The ionexchange agent may be an ammonia adsorbent material in powderized form.The strips of corrugated cardboard are formed by cutting sheets ofcardboard into strips so that the corrugations between parallel outerpanels remain intact. The strips or pieces are then mixed with the ionexchange agent so that it is distributed on the outer and inner surfacesof the cardboard strips and inside the corrugations of the cardboard.The corrugated air-containing structure of the cardboard pieces providescushioning and shock absorption which relieves stress on animal hoovesand legs, and promotes healing of lame animals without the need forexpensive alternate stall flooring such as rubber mats.

[0011] The animal bedding material of the present invention is producedby feeding sheets of cardboard into a shredding or cutting device thatperforms at least two different cutting operations. In one such device,a first set of blades cuts the sheets of cardboard into strips which arethen cut with a second set of blades to a desired length. Paper fiberdust is removed from the strips or pieces by a vacuum system, and thepieces are combined with an ion exchange agent in powder or particulateform. The bedding material composition is then packaged in a sealedcontainer or bag for delivery to a stall and distributed directly upon astall floor.

BRIEF DESCRIPTION OF THE FIGURES

[0012]FIG. 1 is a diagrammatic view of apparatus for producing an animalbedding composition according to the method of the present invention;

[0013]FIG. 2 is a perspective view of a sheet of corrugated cardboardused to make the animal bedding composition of the present invention;

[0014]FIG. 3 is a cross sectional view of a single piece of the animalbedding composition of the present invention, and

[0015]FIG. 4 is a block diagram of a manufacturing process for producingthe animal bedding composition of the present invention.

DETAILED DESCRIPTION OF PREFERRED AND ALTERNATE EMBODIMENTS

[0016] Referring to FIGS. 1 through 4, an animal bedding composition anda method of making the animal bedding composition of the presentinvention is illustrated. A sheet of corrugated cardboard material 10 isprovided. As shown in FIG. 2, the sheet of cardboard is comprised of afirst edge 12, a second edge 14, and a plurality of corrugations 16. Thecorrugations 16 are generally parallel to the first edge 12 and thesecond edge 14 and extend the length of the sheet of corrugatedcardboard 10. The cardboard 10 may be new or recycled stock of two panelsandwiched corrugations ranging in total thickness from approximately{fraction (1/16)}″ to ½″. The outer panels are preferably kraft paper (atough paper made from sulfate wood pulp) or other fibrous cellulosicmaterial ranging in thickness from approximately {fraction (1/32)}″ toapproximately ⅛″. The internal corrugated layer, known as fluting, isalso preferably made of kraft paper or other fibrous, cellulosicmaterial with a flute height, as measured from one interior side of anoverlying panel to an opposing side of a parallel overlying panel, in arange of approximately {fraction (1/16)}″ to ¼″. Preferably, thecorrugated cardboard used for the composition of the invention is aC-flute size of approximately {fraction (3/16)}″ height. Although shownwith corrugations 16 in a general sinusoidal form, other configurationsof the internal layer are possible, or any other structure which createsan air gap between the outer panels, as further described herein.

[0017] With reference to FIGS. 1 and 4, one or more sheets of corrugatedcardboard 10 is fed into a shredder 12. One type of shredding devicewhich can be used in the method of this invention is the Cross Shredmanufactured by Industrial Paper Shredders, Inc. of Salem, Ohio.However, other brands of shredders or other types of cutting devices maybe used. The Cross Shred is capable of accepting cardboard sheets havinga maximum width of about 20 inches and incorporates a two blade cuttingsystem which first cuts the cardboard sheet into strips with a width inan approximate range of ⅛inch to 1 inch or greater, and then chops orcuts the strips into particles having a length in an approximate rangeof ¼inch to about 1 inch or greater. The sheets of corrugated cardboard10 are fed into the shredder 12 with the corrugations 16 generallyperpendicular to a first set of blades in the shredder 12. Sheets ofcorrugated cardboard 10 may be fed individually into the shredder, or aplurality of sheets may be stacked and fed simultaneously into theshredder 12. Using the Cross Shred machine, it is preferred that no morethan three stacked sheets of corrugated cardboard 10 be fed into theshredder at a time. If more than three sheets of corrugated cardboard 10are fed into the Cross Shred, the corrugations may be crushed, thusdiminishing the shock absorption and wicking aeration action of thecorrugated cardboard as further described herein. However, other cuttingor shredding devices may allow more than three sheets of corrugatedcardboard to be cut simultaneously without crushing the internalcorrugated layer. The sheets of corrugated cardboard are cut into stripsof about ⅜inch in width. The ⅜inch wide strips are then cut into pieces18 having a length of about ½inch to about 1 inch.

[0018] The pieces 18 then exit the shredder 12 at the exit point 20 andare transferred to a conveyor belt 21. A vacuum system 22 is provided atan exit point 20 from the shredder to remove and collect any paper fiberdust particles resulting from the shredding of the cardboard 10. Thepieces 18 are then transferred by conveyor belt 21 to mixing containers26 and mixed with an ion-exchange additive in powder form as may beapplied from a dispensing device 24 positioned proximate to conveyor 21whereby the additive is disposed on the particles 10 and inside thecorrugations 16. The dispensing device 24 may be shrouded to contain thepowder particulates of the ion exchange agent as it is applied to thepieces. In a mass production set-up, containers 26 may be supported on amoving carousel or conveyor so that once a container is filled, it isautomatically advanced to a closing or sealing station whereat thecontainer or bag is sealed and removed from the conveyance andpalletized for shipment.

[0019] One particular form of an ion-exchange agent which has beendiscovered to be especially well-suited for the inventive composition isone or more forms of the natural substance zeolite. Zeolites arenaturally occurring volcanic minerals or synthesized materials whichcontain hydrogen, oxygen, aluminum and silicon arranged in athree-dimensional interconnecting lattice structure. Zeolites have theability to selectively adsorb specific gas molecules and the ability toreversibly adsorb and desorb water. One particular form of zeolite,clinoptilolite is most preferred for use in the present invention due toits high selectivity for ammonium ions. However, other zeolites such assynthetic zeolites F and W may be used. Clinoptilote is non-toxic,edible and easily digested and has been used as a food supplement forcattle and swine to improve metabolism and lessen bloating. As such, itis safe and does not pose the health problems associated with other odorcontrol additives such as lime. Ammonium ions are adsorbed by theclinoptilolite, reducing the amount of airborne ammonia typically foundin areas where animals are housed. The reduction of airborne ammoniareduces respiratory distress it is proven to cause.

[0020] Zeolites, and in particular clinoptiloite, also has excellentagricultural fertilization properties. This is critical to the successof a stall material as it must be economically disposed of. In otherwords, acceptance of used stall material by agricultural growers isrequired in order for a stall material to be used in large quantities.Clinoptilolite is high in potassium as major exchangeable cation,providing slow release potassium, and nitrogen when pre-loaded withammonium.

[0021] Preferably, the containers 26 are filled with pieces 18 to about50% of capacity and about 50% of a predetermined amount of ion exchangeagent in powder form is added to the pieces 18. The containers 26 arethen completely filled with pieces 18 and the remaining ion exchangeagent powder is mixed in. The ion exchange agent can alternatively bedistributed on the pieces 18 using a sifting mechanism as the pieces 18are moved along conveyor belt 21. A preferred form of the animal beddingcomposition may have from about ½ounces to about 8 ounces ofclinoptilolite per 3 cubic feet of pieces 18, preferably from about 1ounce to about 3 ounces of clinoptilolite per 3 cubic feet of pieces 18.

[0022]FIG. 3 shows a piece 18 of the animal bedding composition. As usedherein, the term “composition” means the combination of the cardboardpieces and the particles 25 of the ion exchange agent. As illustrated, acorrugated cardboard structure includes outer generally parallel panels31 with inner surfaces 30 and outer surfaces 32, and an inner panel 35having a plurality of corrugations 34. The corrugations 34 each have afirst surface 36 and a second surface 38. The height of the corrugations34 from one inner surface 30 to the opposing inner surface 30 of panels31 dictates the thickness of the cardboard structure. For purposes ofpracticing the invention, a corrugated cardboard structure with arelatively greater or increased thickness is preferred. Increasedthickness provides a mechanical benefit of shock and pressureabsorption, and provides a greater amount of internal surface area as acarrier structure for a powderized form of an ion exchange additiverepresented schematically, not to scale, as particles 25. The particles25 are, through mechanical mixture, carried by and attached to thecorrugated cardboard pieces 18 to form the composition.

[0023] The ion exchange agent particles 25 are disposed on the inner andouter surfaces 30 and 32, and on the inside and outside surfaces 36 and38 of the corrugations 34. As explained, the preferred ion exchangeagent is zeolite, and the most preferred zeolite is clinoptilolite.Clinoptilolite is preferred due to its excellent ammonia adsorptioncapability. When the zeolite is mixed with the corrugated pieces 18, anddistributed on the inner and outer surfaces 30 and 32, and on the insideand outside surfaces 36 and 38 of the corrugations 34, the absorptionproperties of the cardboard are combined with the adsorption propertiesof the zeolite. Moisture is absorbed by the cardboard and adsorbed bythe zeolite. This combined moisture absorption/adsorption is furthercombined with the mechanical cushioning and shock absorption of thecorrugated structure. Further, it has been discovered that there issufficient mechanical bonding between the adsorbent, deodorizing zeolitematerial and the external and internal surfaces of a corrugatedcardboard structure such that the cardboard acts as both a carrier anddistributor of the adsorbent, deodorizing zeolite material throughoutthe area of distribution of the shredded particles. It has also beendiscovered that, in the animal stall application as described, thecorrugated cardboard structure provides a hydrodynamic wicking action toaerate and evaporate moisture from the stall floor. As the pieces 18become wet, the air gaps between the outer panels 31 and the innercorrugated layer 34 allow air to pass through each piece to evaporatemoisture. The presence of the zeolite within the air gaps of the pieces18 increases the amount of ammonium ion exchange which occurs, thusmaximizing the reduction of ammonia odor and respiratory distress.

[0024] When the composition is distributed about a stall floor, asubstantial amount of the zeolite remains disposed on all surfaces ofeach piece 18. It is desirable that a portion of the zeolite also fallon the stall floor. Part of the animal waste is absorbed by the shreddedcardboard and part of the waste works its way through the beddingmaterial to the stall floor. The zeolite on the stall floor adsorbsammonium from the waste that has fallen to the stall floor. The beddingmaterial acts as a wick, slowing absorbing waste from the stall floor.The corrugations allow for air flow and slow drying, so that the piecesdo not mat together.

[0025] The animal bedding composition can be spread upon a stall floorin any thickness, such as approximately 2 inches or up to 10 inches orgreater depending on the type of animals housed. For example, in stallsfor show or race horses, it is desirable to have a thicker layer ofbedding to provide more support and cushion. The composition isperiodically remixed or agitated in the stall to redistribute both thecardboard pieces and the particulates of ion exchange agent. When thecomposition becomes soiled with animal waste, it is collected and usedas an agricultural fertilizer in direct soil applications. For example,when a portion of the composition within a stall is soiled, it isremoved by pitch fork or shovel in the ordinary manner of “mucking out”.The removal composition is replaced by a fresh supply of equal quantity.The soiled composition is ideally suited as a fertilizer for growingvegetables and especially mushrooms. This is due to the high carboncontent of the kraft paper of which the corrugated cardboard isconstructed and the excellent fertilizing properties of zeolite as aslow release of nitrogen and potassium. The carbon bonds to nitrogenpresent in urine, thus the urine soaked bedding composition is anitrogen-rich fertilizer. As mentioned, critical to the superiorperformance of the composition as a vegetable and mushroom fertilizer isthe absence of wood shavings which are not as rapidly biodegradable ascardboard. Stall materials which contain wood shavings are notacceptable to agricultural growers. Thus, wood shavings when used installs must be kept segregated from other materials.

[0026] The animal bedding composition of the invention is easier tospread on stall floors than the prior art bedding materials. Unlike hayand straw, the cardboard pieces do not clump together. As such, it isnot necessary to separate the pieces after the material is poured ontothe stall floor. This also makes the waste removal or “mucking out”procedure simpler. Because the individual pieces of the bedding materialdo not stick together, the animal waste separates from the beddingmaterial more readily. As a result, relatively less material is neededto replenish the bedding. Also, the resulting waste is less bulky thanwith other bedding materials because a relatively large amount of thebedding material remains on the stall floor after the animal waste isremoved.

[0027] Accordingly, the preferred and alternate embodiments of thepresent invention have been described. With the foregoing description inmind, however, it is understood that this description is made only byway of example, that the invention is not limited to the particularembodiments described herein, and that various rearrangements,modifications and substitutions may be implemented without departingfrom the true spirit of the invention as hereinafter claimed.

We claim:
 1. An animal bedding composition for distribution upon ananimal stall to provide a hygienic support medium, the animal beddingcomposition comprising a plurality of corrugated cardboard pieces and atleast one ion exchange agent in particulate form interspersed with thecorrugated cardboard pieces whereby the ion exchange agent is carried bythe corrugated cardboard pieces for even distribution about a floor ofan animal stall.
 2. The animal bedding composition of claim 1 whereinthe cardboard pieces are comprised of corrugated cardboard having outerpanels and internal corrugations, the pieces cut so that the internalcorrugations remain intact.
 3. The animal bedding composition of claim 2wherein the ion exchange agent is disposed on outer and inner panels ofthe strips of cardboard and on outer and inner surfaces of the internalcorrugations.
 4. The animal bedding composition of claim 3 wherein thecardboard pieces have a length of approximately ⅛to 1 inch and a widthof approximately ¼inch to ¾inch.
 5. The animal bedding composition ofclaim 1 wherein the internal corrugations of the corrugated cardboardhave a height dimension in a range of approximately {fraction(1/16)}inch to about ½inch.
 6. The animal bedding of claim 1 wherein theion exchange agent is a zeolite.
 7. The animal bedding composition ofclaim 1 comprising between about ½ounce to about 8 ounces of ionexchange agent and about 3 cubic feet of corrugated cardboard pieces. 8.The animal bedding composition of claim 1 wherein the ion exchange agentis clinoptilolite.
 9. The animal bedding composition of claim 1 whereinthe corrugated cardboard is constructed of kraft paper.
 10. The animalbedding composition of claim 1 wherein the corrugated cardboard and ionexchange agent are combined in an approximate ratio of 1 to 10 ounces ofion exchange agent per 3 to 6 cubic feet of corrugated cardboard pieces.11. The animal bedding composition of claim 1 in combination with ananimal stall wherein the composition is distributed over a floor of thestall at an average approximate thickness in a range of 1 to 10 inches,and a portion of the ion exchange agent carried by the corrugatedcardboard pieces is placed in contact with the stall floor.
 12. Theanimal bedding composition of claim 1 wherein the corrugated cardboardpieces are randomly oriented upon and above a stall floor and operativeto collapse upon compression under weight such as applied by an animalin the stall.
 13. An animal stall composition for use as a floorcovering to provide substantially dust free cushioning, moistureabsorption and adsorption and odor control, and to render aready-to-apply agricultural fertilizer in waste form, the animal stallcomposition comprising a plurality of pieces of kraft paper in amultiple panel structure having outer generally parallel panels and aninternal panel connected to the outer panels and providing an air gapbetween the outer panels, and an ion exchange agent in a particulateform interspersed with the pieces and substantially in contact with allsurfaces of the pieces, whereby the ion exchange agent is carried by thepieces when distributed upon a stall floor, and air and moisture withina stall contacts the kraft paper of the pieces and the ion exchangeparticulates on the pieces providing a moisture and odor reductionprocess.
 14. The animal stall composition of claim 13 wherein the piecesof kraft paper have a fluted corrugated structure.
 15. The animal stallcomposition of claim 13 wherein the pieces of kraft paper are cut in aconfiguration in which an internal structure which separates the outerpanels is preserved.
 16. The animal stall composition of claim 13wherein the ion exchange particulates are present on internal andexternal surfaces of the kraft paper pieces, and excess ion exchangeparticulates are carried by the pieces for distribution upon a stallfloor.
 17. The animal stall composition of claim 13 , in combinationwith animal waste wherein the kraft paper contains nitrogen from urineas a result of carbon content of the kraft paper, and the ion exchangeparticulates contain ammonium ions and nitrogen.
 18. The animal stallcomposition of claim 13 distributed about a floor of a stall, with aportion of the ion exchange particulates carried by the kraft paperpieces upon the floor and a portion of the ion exchange particulates incontact with the kraft paper pieces.
 19. A method of making animalbedding composition for use as a hygienic ergonomic floor cover inanimal stalls, the method comprising the steps of: providing sheets ofcorrugated cardboard having outer panels and internal corrugations;cutting the sheets of corrugated cardboard into pieces so that theinternal corrugations remain intact; removing dust particles from thepieces; and mixing an ion exchange agent in powder form with the piecesso that the ion exchange agent is disposed on outer and inner panels ofthe pieces and on outer and inner surfaces of the internal corrugationsof the corrugated cardboard.
 20. The method of claim 8 wherein thecutting step comprises the steps of: providing a shredder having firstblades and a second blades; feeding the sheets of cardboard into theshredder so that the internal corrugations are generally perpendicularto the first blades; cutting the sheets of cardboard into strips withthe first blades; and cutting the strips to approximately 1 inch inlength with the second blades.
 21. The method of claim 9 wherein thezeolite comprises clinoptilolite.
 22. The method of claim 10 wherein theamount of zeolite is approximately 1 ounce to about 8 ounces per 3 cubicfeet of cardboard strips.